While the cause of death remains a mystery, police tell People that “at this time, there’s no obvious evidence of foul play.”

Beverly Hills Police Lieutenant Mark Rosen said Saturday “someone in her entourage found her unresponsive in her room. … Our detectives are still in the room, and her body is still here as well. I can confirm that Whitney Houston was pronounced dead at 3:55 p.m. this afternoon at the Beverly Hilton Hotel. We received a call at 3:43 p.m. from hotel security and Beverly Hills Fire, and police responded minutes later.”

Police note that an investigation is ongoing. TMZ reports that while no illegal drugs were in her hotel room, prescription drugs were found. Sources add that she may have drowned in the bathtub, where her body was reportedly discovered.

Houston’s body had been removed from the tub when authorities arrived, so an autopsy will have to be performed to determine the cause of her death. TMZ added that she had reportedly been taking Xanax at the time. Houston had been spotted drinking the night before at a pre-Grammy party, and in combination with the prescription drug, it could have led to her falling asleep in the tub and drowning.

Bobbi Kristina, Houston’s daughter with ex-husband Bobby Brown, was reportedly on the hotel premises when Houston died. According to TMZ, Bobbi got into an argument with police when she was denied access to see her mother’s body. Houston’s cousin, Dionne Warwick, also showed up, according to reports, and was also not allowed to see the superstar’s body.

On Sunday night (February 12), fellow Davis protégé Jennifer Hudson and Houston’s longtime friend Chaka Khan are expected to lead a tribute to the late icon during the 2012 Grammy Awards.

Grammy executive producer, Ken Ehrlich, said in a statement, “It’s too fresh in everyone’s memory to do more at this time, but we would be remiss if we didn’t recognize Whitney’s remarkable contribution to music fans in general, and in particular her close ties with the Grammy telecast and her Grammy wins and nominations over the years.”